Stroke-end programmer for machine tool

ABSTRACT

A device is disclosed for programming the terminal portion of the operative stroke of the tool in a machine tool equipped with hydraulic driving means. The stop motion comprises essentially a discharge valve responsive to a control wedge rigid with said tool and adapted to engage a stop member of which the position is determined in succession by the various adjustable studs carried by a rotary barrel. The barrel is simply laid upon a pair of cradle-forming rollers, at least one roller being driven from the means controlling the angular position of said barrel; if desired, a plurality of similar barrels corresponding to different predetermined programmes may be provided.

Cailloux 1451 Apr. 1, 1975 1 STROKE-END PROGRAMMER FOR MACHINE TOOL [75]lnventor: Paul Cailloux, La Varenne Saint-Hilaire, France [73] Assignee:Promecam Sisson-Lehmann,

Saint-Denis. France 1221 Filed: 11111115, 1974 1211 Appl. N0.;47s,107

3.165.140 1/1965 Hazel 1 1/1965 10/1973 Bridges 72/441 PrimaryExaminerC. W. Lanham Assistant Examiner-Gene P. Crosby Attorney, Agent,or Firm-Michael S1 Striker [57] ABSTRACT A device is disclosed forprogramming the terminal portion of the operative stroke of the tool ina machine tool equipped with hydraulic driving means. The stop motioncomprises essentially a discharge valve responsive to a control wedgerigid with said tool and adapted to engage a stop member of which theposition is determined in succession by the various adjustable studscarried by a rotary barrel. The barrel is simply laid upon a pair ofcradle-forming rollers, at least one roller being driven from the meanscontrolling the angular position of said barrel; if desired, a pluralityof similar barrels corresponding to different predetermined programmesmay be provided.

7 Claims, 7 Drawing Figures Voth 72/389 Fff'ENIEU APR 1 [9?5 SHEET 1 0f3 DDUCIEIEIDE] EDI Hmfl. w

STROKE-END PROGRAMMER FOR MACHINE TOOL The present invention relates ingeneral to devices for programming the terminal portion of the stroke ofthe tool in a machine tool. with a view to cause said tool to accomplisha series of strokes of different lengths during a predetermined cycleand thus perform each time a different operation or a specific work. forexample a sequence offolding or bending steps or operations throughdifferent angles in the specific case ofa bending press or like machine.

This device is intended for equipping machine tools comprising hydrauliccontrol means for actuating the movable tool through one or morecylinder and piston units.

At present. machine tools are known which comprise control means of thischaracter and other means for stopping the machine tstop-motion devices)at the end of its operative stroke. in the form of a release ordischarge valve inserted in the hydraulic circuit of said driving unitor units and adapted to be actuated by a control member rigidlyconnected to said movable tool. Preferably, this member consists of awedge adapted to bear against a positioning stop member adjustable forproperly actuating said valve. Thus. the assembly can be adjusted bysimply changing the position of said stop member with a view to causethe tool to be stopped in a predetermined position.

It is clear that a system of this type is particularly advantageous inmany types ofmachine tools and notably in bending presses or the like.However, the adjustment of said stop member. engaged by said controlwedge. must obviously be modified each time it is desired to change thestopping position of the movable tool.

Under these conditions. this known arrangement is scarcely adequate forperforming a series of successive different operations on a sameworkpiece. for instance a series of folding movement performed atdifferent angular values on a same sheet-metal workpiece. It istherefore the essential object of this invention to provide a devicecapable of programming different final stroke movements of the movabletool of a machine tool during a predetermined cycle of operations. witha view to perform different successive works or operations on a sameworkpiece. However. this invention is also concerned with means capableof modifying very rapidly an existing programme with a view toaccomplish different works or operations.

To this end. the present invention is directed to provide means forprogramming the terminal fraction of the stroke of a movable tool in amachine tool equipped with a hydraulic control system comprising a stopmotion in the form of a release or discharge valve responsive to acontrol wedge rigid with said tool and adapted to engage a stop memberof which the position is determined in succession by various adjustablerods or studs carried by a rotary barrel. this device beingcharacterised in that said barrel is detachably laid upon a pair ofrollers constituting a supporting and holding cradle. at least one ofsaid rollers being driven from the means controlling the angularposition of said barrel. the arrangement comprising a series of similarinterchange able barrels corresponding to different predeterminedprogrammes.

On each barrel the position of the various stop rods is adjustablebeforehand in various ways in order to determine a precise programme ofthe limit stroke positions of the movable tool of the relevant machineduring the various movements performed by said tool during a same cycle.

According to another feature characterising this device the barrelcontrol system comprises a stop member. for example in the form ofamicroswitch inserted in the control circuit of the relevant motor andadapted to be actuated by each stop stud when the latter has reached itspredetermined working position, inasmuch as it actually projects fromits barrel.

Under these conditions it is possible to neutralize or disengage anumber of barrel rods by retracting these studs completely. Thus. inoperation. the barrel continues its rotation when the retracted studsattain their theoretical operative position in which they register withthe movable stop member. With this arrangement. it is thus possible tomodify at will the number of programmed operations.

However, other features and advantages of the pres ent device willappear as the following description of a typical embodiment thereofproceeds. This description is given by way of example with reference tothe attached drawings. in which:

FIG. 1 is a diagrammatic front elevational view of a bending pressequipped with the programming device of this invention;

FIG. 2 is a vertical section and elevational view of the same device;

FIG. 3 is a section taken along the line lIl-IIl of FIG. 2:

FIG. 4 is an elevational view of a detail of the present device; FIGS. 5and 6 are elevational views. i.e.. a side elevational and an end view.respectively, of a member associated with the control barrel. and

FIG. 7 is a fragmentary section taken along the line VllVII of FIG. 5.

In the example illustrated in FIG. 1 the device according to thisinvention is used for controlling a bending press having a fixed bendingbeam 1 rigid with the frame structure 2 of the machine, and a movablebending beam 3. The movements or strokes of this movable bending beam 3are produced by means of a hydraulic cylinder and piston actuator unit4, and a central guiding member 5 is also provided.

The hydraulic circuit 6 of cylinder and piston unit 4 comprises arelease or discharge valve 7 constituting an integral component elementof the programming device of this invention. This valve 7 comprises acontrol member in the form of a push-member 8 and is secured to theframe structure 2 of the machine. for example behind the movable lowerbeam 3.

This movable lower beam 3 carries an arm 9 (FIG. 2) having one endpivoted to a pivot pin 10 carried by this beam and the opposite endengaged and movable between the push-member 8 of valve 7 and a roller 11carried by the first end of a rod 12 adapted to constitute a bearingstop member.

However, the upper end of arm 9 comprises a ramp or cam face 13engageable by the roller 11. Thus, this arm 9 acts somewhat like a wedgemember capable of actuating the valve 7 by reacting against the rollerof stop member 12. Preferably, a blade 14 having a fixed position isinterposed between the upper end of said arm or wedge 9 and saidpush-member 8 of valve 7 for preventing a direct frictional contacttherewith during the movements of the movable tool.

The rod 12 extends at right angles to the axis of movement of wedge 9and is slidably mounted in a guide bearing 15 rigid with a member 16forming an integral part of the frame structure of the machine. However,a spring 17 attached to a fixed member 18 constantly urges the stopmember 12 for engagement with the cam face 13 of wedge 9. A link 19 isalso provided for guiding the corresponding end of said stop member 12.

At its second end opposite said roller 11 the stop member 12 carries ablock 20 provided with a pin 21 for the purpose of preventing therotation of said stop member about its axis. This block 20 registerswith a rotary barrel 22 constituting the main component element of theprogramming device ofthis invention. This barrel 22 carries a series ofscrews 23 adapted to constitute as many studs projecting from the barrelend face registering with said block 20. The arrangement is such that ineach angular position of said barrel only one stud thereof is adapted toact as a stop member for engagement by the block 20 when said rod 12recedes in its bearing 15 as a consequence of the thrust exerted by thewedge 9. Thus, in the position illustrated in FIG. 2 only the lower stud23a can act as a stop member to said block 20.

The position of these various barrel studs is adjust able so that theycan project more or less from the front face of the barrel body. To thisend. the screw end of each stud 23 has a socketed end engageable by acorresponding key 24 disposed in a waiting position on a support 25rigid with the housing 26 enclosing the barrel 22 and the otherancillary members of the present device. said housing being of coursefastened to the frame structure of the machine.

The barrel 22 is detachably mounted and to this end it is simply laidupon a pair of parallel rollers 27a. 27b constituting a kind of cradle.However, one of these rollers. notably roller 27b. is adapted to drivesaid barre l 22 for rotation about its axis by being driven in turn viaan endless belt 28 from the output shaft of a motor and reduction-gearunit 29.

On the side opposite said block 20. the barrel 22 en' gages anadjustable socket 30 so that when necessary the position of all theprojecting studs 23 carried by said barrel 22 can be modified to thesame extent. The socket 30 is adapted to slide in a support 3! rigidwith the housing 26 and to be locked in the desired position by means ofa stop screw 32.

The control circuit of the barrel driving motor 29 comprises amicroswitch 33 of which the control member 34 is adapted to be actuatedby the projecting stud 23a of said barrel, provided that this stud is inits operative position and projects sufficiently therefrom, so that itcan positively stop the backward movement of said movable stop member12. Under these conditions, the microswitch 33 is not actuated by thosebarrel studs 23 which are in their inoperative position.

The portion of the surface of block 20 which registers with the positionof a stud 23a in operative position carries a plate 35 adapted toconstitute a contact face. A spring 36 is interposed between this faceand the block, so that the plate 35 tends to move away there from whenthe adjustable stop 12 resumes its normal waiting position.

Now the movable plate 35 comprises a member adapted to actuate amicroswitch 37 each time said plate is thus released. This microswitch37 is inserted in the control circuit of motor 29 in order to re-startsame at that time.

The positions of the various projecting studs 23 are adjusted when eachstud is in the operative position 5 23a. This constitutes an essentialadvantage characterising this device, for the adjustment is made whenthe movable tool is exactly in the position in which it is to bestopped.

By means of the above-mentioned key 24 the corresponding stud 23 isscrewed in or out until it engages the contact plate 35 of block 20, ina position suitable for retaining the adjustment stop member 12 so thatthe latter acts at that time as a fixed bearing surface and the wedge 9engages the push member 8 ofdischarge valve The same adjustmentoperation must be carried out for each one of the eight projecting studs23, if it is contemplate to bend the same workpiece eight times, insuccession, during each cycle. However, if a smaller number of bendingsteps are contemplated a proper number of projecting studs 23 must bemoved to their retracted position so that only the necessary numberthereof are available for the desired cycle.

Due to the specific mounting contemplated for the barrel 22 the deviceaccording to this invention may advantageously comprise a plurality ofsuch barrels, all identical but adapted to carry out differentpredetermined programmes. Thus, each time it is only necessary to removeone of these barrels and to substitute another barrel therefor which issimply laid upon the pair of rollers 27a and 27b.

The device operates as follows:

When the movable beam 3 of the press rises as a consequence oftheoperation of the hydraulic cylinder and piston unit 4, the wedge member9 is inserted more deeply between the push member 8 of the discharge orrelease valve 7 and the bearing stop 12.

However, this has no consequence whatsoever as long as this bearing stop12 can recede. i.e.. until it engages the projecting stud 23a of barrel23 which is thus in its operative position. When the contact plate 35 ofblock 20 engages this stud, the wedge 9 cannot move the stop member 12further, and is thus caused to actuate the mush member 8 of valve 7, sothat the control circuit of actuator 4 is exhausted and the movable beam3 is stopped immediately.

Under these conditions, the movable beam 3 will be stopped exactly inthe desired position for performing the bending step corresponding to apredetermined angle. After this bending step the operator may controlthe downward stroke of the movable beam 3, and thus the latter will movedownwards bodily with the wedge 9, so that the valve 7 is re-closed.However, at the same time the contact plate 35 of block 20 resumes itsinoperative position, thus closing microswitch 37 and consequentlyrestoring the operation of motor 29 driving the barrel 22 for rotationabout its axis.

Nevertheless, this barrel 22 is rotated only through a limited angularamplitude sufficient however for bringing another stud 23 to itsoperative position 230 in lieu of the preceding stud. In fact, when thisother stud 23 assumes this operative position, it engages themicroswitch 33 and thus the motor 29 is stopped immediately. Therefore,it is another projecting stud that will accurately determine the nextultimate position of the movable beam 3, under the same conditions asset forth hereinabove.

In connection with the foregoing it may be reminded that the projectingstuds 23 brought to their retracted inoperative position do not actuatethe microswitch control member 34, whereby in this case the barrel 22can perform an angular movement of greater amplitude until anotherprojecting studs is brought to the operative position.

The outer periphery of barrel 22 has formed therein a series of severalgroups of notches adapted to actuate control members 38 associated witha plurality of microswitch 39 inserted in the various circuits ofadisplay system according to the conventional binary code method. Thisdisplay is visible on a sequence indicator mounted in a control boardadapted to be installed in any desired and suitable location at somedistance from the machine. and connected via a flexible cable 40 to thedevice.

Preferably. the notches (or llat faces) 41 adapted to actuate thecontrol members of microswitches 39 are formed on the outer peripheralsurface of a socket 42 fitted around the body of barrel 22. Each groupof notches corresponds to one of the projecting studs 23 and. accordingto the specific case involved. includes one or a plurality of notchessuitably disposed for producing the display contemplated according tothe binary code method.

Ho\ve\ er. the control board may also advantageously comprise a knob formanually controlling the barrel and also another knob for preventing atwill the automatic rotation of the barrel between two strokes of the mo\able tool in order to ensure a repetition of the tool action.

From the foregoing it appears clearly that multivarious possibilities ofuse of a machine tool can be derived from this device. since. inaddition to a programmed stroke end of the movable tool it also affordsa repetition ofeach working pass or alternatively the performance of apartial operation by neutralising some of the barrel studs.

In any case. with the adjustable socket 30 it is also possiblesimultaneously to shift by a same value the position of the variousprojecting studs of barrel 22, for example to take due account ofavariation in length in a series of workpieces to be bent. or variationsin the viscosity of the fluid circulating in the hydraulic circuit, orany other factors or parameters likely to entail a modification in thefinal result.

Moreover. the programmed control device of this invention mayadvantageously be combined with means for adjusting the non-programmedstroke end or limit.

These means advantageously comprise a rod 43 reg istering with the block20 of stop member 12, and more particularly with the portion of thesurface of this block which is not covered by the contact plate 35.

This rod 43 is screwed in a fixed support 46 and rigid with a rotary cap44 rotatably mounted on said support. This cap 44 carries a controlcrank handle 45 whereby the position of said stop rod 43 can be adjustedat will. ()l'course. when this manual adjustment system is operative thebarrel 22 must be removed, but it is also possible to dispose all thestuds 23 thereof in their retracted inoperative position.

conversely. when it is desired to use the programming system comprisingthe barrel 22, the control rod 43 must be disconnected or neutralised byretracting same to its fully inoperative position.

As already mentioned hereinabove, the present device is advantageous,inter alia, in that it permits of programming the terminal portion ofthe stroke of the movable beam ofa press as illustrated in FIG. 3 duringa series of movements forming a same cycle, with a view to bend severaltimes a same workpiece according to different, increasing angularamplitudes. However. it may also be emphasized that the same device maybe used for programming different machine tools in a similar manner.Besides. it will readily occur to those conversant with the art that allmachine tools equipped with the device of this invention are alsocovered by the present invention and fall within the scope thereof.

What is claimed as new is:

1. Device for programming the terminal portion of the stroke of the toolof a machine tool equipped with a hydraulic control system incorporatinga stop-motion consisting essentially of a discharge valve. said devicecomprising:

a movable stop member comprising a first end disposed in front of saiddischarge valve and a second end on opposite side.

control wedge rigid with said tool and movable be tween said first endof said stop member and said discharge valve and adapted to actuate saidvalve by reacting against said first end of said stop mcmber.

a rotary barrel disposed in front of said second end of said stopmember.

a plurality of parallel adjustable studs carried by said rotary barrel.

a pair of parallel rollers constituting a cradle for supporting saidbarrel laid detachably upon said rollers driving means adapted to driveat least one of said rollers, whereby said adjustable studs are broughtsuccessively in operative position in front of said stop member.

2. Programming device as set forth in claim 1 further comprising aseries of similar interchangeable barrels corresponding to a pluralityof predetermined programmes.

3. Programming device as set forth in claim 1. wherein said drivingmeans. of at least one of said rollers comprise a motor and said devicefurther comprises a first microswitch inserted in the energizing circuitof said motor and adapted to be actuated by each stud projecting fromsaid barrel when the stud involved is in its operative position andinasmuch as it actually projects from said barrel.

4. Programming device as set forth in claim 3, wherein said barreldriving motor control circuit comprises a second microswitch adapted tobe actuated by said movable stop member when the latter is returned toits waiting position by a return spring after each operation of themachine.

5. Programming device as set forth in claim 4, wherein said second endof said movable stop member which is adjacent to said barrel carries acontact plate mounted on one or a plurality of spacer springs andadapted to actuate the microswitch controlling the energization of thebarrel driving motor.

6. Programming device as set forth in claim 5. wherein, on the sideopposite to said movable stop member. said barrel bears against anadjustable socket adapted. by modifying its position, to simultaneous 78 change to the same extent the position of the end of all tool controlsystem comprising an adjustable rod the Studs prolecung from Send barre"adapted to be retracted completely when it is desired 7. Programmingdevice as set forth in claim 5, further comprising a non-programmedmanual system for controlling the terminal position of the movable tool.said to operate the programmed control device.

1. Device for programming the terminal portion of the stroke of the toolof a machine tool equipped with a hydraulic control system incorporatinga stop-motion consisting essentially of a discharge valve, said devicecomprising: a movable stop member comprising a first end disposed infront of said discharge valve and a second end on opposite side, controlwedge rigid with said tool and movable between said first end of saidstop member and said discharge valve and adapted to actuate said valveby reacting against said first end of said stop member, a rotary barreldisposed in front of said second end of said stop member, a plurality ofparallel adjustable studs carried by said rotary barrel, a pair ofparallel rollers constituting a cradle for supporting said barrel laiddetachably upon said rollers, driving means adapted to drive at leastone of said rollers, whereby said adjustable studs are broughtsuccessively in operative position in front of said stop member. 2.Programming device as set forth in claim 1 further comprising a seriesof similar interchangeable barrels corresponding to a plurality ofpredetermined programmes.
 3. Programming device as set forth in claim 1,wherein said driving means, of at least one of said rollers comprise amotor and said device further comprises a first microswitch inserted inthe energizing circuit of said motor and adapted to be actuated by eachstud projecting from said barrel when the stud involved is in itsoperative position and inasmuch as it actually projects from saidbarrel.
 4. Programming device as set forth in claim 3, wherein saidbarrel driving motor control circuit comprises a second microswitchadapted to be actuated by said movable stop member when the latter isreturned to its waiting position by a return spring after each operationof the machine.
 5. Programming device as set forth in claim 4, whereinsaid second end of said movable stop member which is adjacent to saidbarrel carries a contact plate mounted on one or a plurality of spacersprings and adapted to actuate the microswitch controlling theenergization of the barrel driving motor.
 6. Programming device as setforth in claim 5, wherein, on the side opposite to said movable stopmember, said barrel bears against an adjustable socket adapted, bymodifying its position, to simultaneous change to the same extent theposition of the end of all the studs projecting from said barrel. 7.Programming device as set forth in claim 5, further comprising anon-programmed manual system for controlling the terminal position ofthe movable tool, said tool control system comprising an adjustable rodadapted to be retracted completely when it is desired to operate theprogrammed control device.